wifi: iwlwifi: mvm: add a debugfs for (un)blocking EMLSR

This is needed for testing purposes.

Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240505091420.eba2b6f0664c.I5f058e02abda11bf2eccfd2bcb59ca26bae87a3a@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>